Attachment for power-operated hammers.



G. W. GIL-MAN & A.

L. WELCH.

' APPLICATION FILED 13.23, 1011.

27 2L V l0 28 52 n 9 55 lO 55 fawwau Patented Nov. 7, 1911.

and in either case the UNITED STATES PATENT OFFICE.

CHARLES W. GILMAN AND ANIS L. WELCH, OF WORCESTER, MASSACHUSETTS,

ATTACHMENT FOR POWER-OPERATED HAMME RS.

Specification of Letters Patent.

Patented Nov. 7, 1911.

Application filed February 23, 1911. Serial No. 610,297.

T 0 all whom it may concern:

Be it known that we, CHARLES W. GIL- MAN and ANis L. WELCH, citizens of the United States, both residing at Worcester, in the county of WVorcester and Stateof Massachusetts, have invented a new and useful Attachment for Power-Operated Hammers, of which the following is a specification.

This invention is designed for the purpose of obviating certain difiiculties met with in operating power operated hammers used largely for forging and similar purposes. It is applicable to hammers driven by steam or compressed air. 'As is well understood the piston rod which is connect,

ed -with the hammer head of this .type of hammer is subjected to extremely rough usage and if it is grooved or scored in order to attach the'hammer the like the metal will soon crystallize at this point and the piston rod will break after a comparatively short life. *It has been attempted to overcome this difliculty by making the end of the piston rod conical and driving it into an opening of the same shape in the hammer head. This does overcome this difliculty, but it introduces an: other, namely,

rod gets loose from the hammer head and then the steam entering under the piston drives the same up against the head of the cylinder either cracking the head or in some cases breaking the cylinder itself. This obviously, is a. rather expensive accident even when only the head is cracked, but when the cylinder is broken it is much more so,

time that the hammeris out of commission is lost, thus adding very materially to the expense.

This invention is designed for the purpose of permitting the use of. the conical ended piston rod without other fastening means and yet preventing the breaking'of the cylinder or cap thereon; to provide'for accomplishing these results in an exceedgly simple manner without really reconstruct ng the hammer in any way or adding greatly to the expense of the machine, and

to provide for driving the rod back into the head when it becomes loose, and auto matically stopping themachine. The inand Fig. 3 is a by means of 'a-pin or:

that occasionally the piston.

venti'on also involves details of construction as will appear hereinafter.

Reference is to be had to the accompanying drawings, in which Figure l is a front elevation of a steam hammer of well-known type with a preferred embodiment of this invention applied thereto; Fig. 2 is a side view of the same; plan of a. portion of the attachment. a

The steam hammeritself need not be described in detail as one of ordinary shown. It is-shown as provided with the usual cylinder 10, piston 11, piston rod 12,

and hammer head 13. The piston rod is form is provided with a conical. end 14 driven into I, I

a similar shaped opening in the hammer head as has been stated-f A valve 15 dea signed to be operated bya treadle Him the like is employed for controlling the hammer. It will be understood, of course, that when the rod 12 gets loose from the" ham- 'mer head the steam entering under the piston 11 will raise the rod much more rapidly than it would with'the heavy weight of the hammer thereon.- In order to prevent the piston from going too high and to drive *the rod back into the' head, a movable pin 20 is introduced into the top of the cylinder through a stufling box 21. For this purpose. a ring 22 is placed on top of the cylinder and a cap 23is secured to it so as-to allow a little more steam space at this point than is customary. The. pin 20 is adjustably mounted on a lever 24, pivoted on a stationary member 25 on the cylinder. The lever is provided witlh a downwardly extending hook 26 connected by a spring 27 under compression with an upwardly extending hook 28 from the stem of the valve 15. A rack 30 is located adjacent to. the lever 24 andthe construction is such that -this-lever normally presses against the rack and when it moves up in a manner to be descrlbed hereinafter it will stay at whatever elevation it reaches. Stops 31 are secured into the base of the cylinder and have eyes 32 at the topwhich receive a valve stem.

In the operation of the device, if the rod 12 gets loose the entrance of steam under thQ'PlStOD. 11 will drivethe'piston upwardly pin 33 on the at a high rate of speed until it strikes the pin 20. This results in reversing the valve 15 through the action of the hooks 26 and 28, but on account of the stop the valves are moved only so far as necessary even though the piston may rise to an unprecedented height. The springs relieve the ar at both ends of the movement. Having raised the valve the lever 24 is held up by the rack and the valve is simply changed to cut off steam from below the piston 11, open the exhaust on that side, and allow steam to enter through: the upper port to the space above the piston. The effect of this obviously is to drive the piston and rod downwardly with great rapidity and to leave it in that position until the operator releases the lever 24 from the rack 30, and

then reverses the valve in the usual manner. In addition to the fact that this simple operation prevents the breaking of the upper part of the cylinder or cap it has another important effect. On account of the rapid-.

ity with which the piston and rod are driven downward, the conical end of the rod is forcibly driven into the hammer head and it has been found in practice that this results in securely fastening these two elements so that upon the subsequent operation of-the device the hammer will be moved with the piston rod and it will be as firmly attached "as it usually is in this class of machinesi While we have illustrated and described a preferredform of theinvention and shown it as applied to a particular type of steam hammer, we are aware that theinvention 'can be carried out imother'forms and can be applied to all types of power operated hammers without departing from. the scope of this invention as expressed .in the claims. Therefore we do not wish to be limited to the details of construction shown or the particular type of'hammer, but

What we do claim is 1. In a power hammer, the combination with a cylinder, piston, valve-forcontrolling the admission of steam or the like to the cylinder, and manually operated means for controlling,the admission of steam through said valve, of independent means connected with said valve for moving it to admit steam on one side of the pistonand exhaust for controlling the operation of. the cylinder, of means'connected with said valve for moving it to admit pressure on one side of the piston andexhaust it from the other {when the piston moves beyond its usual travel in one direction, and means for automatically holding the valve in that position, whereby the piston will be driven back'to the other end of the cylinder and remain there until said valve operating means is re- 70, turned to normal positlon.

3. In a power operated hammer, thdrcombination with the piston, cylinder, and valve for controlling the admission and exhaust of power, with a plunger extending into the cylinder through the end thereof, means yieldingly connected with said plunger for operating said valve to admit power to one side of the cylinder when the plunger is operated and exhaust the other, and means whereby when said plun er has been 0 erated it and the valve will be retaine in the position in which. they are left by the operation of the piston.

4. In a device of the character described, the combination with a cylinder and piston,

of a valve for controlling the operation of the piston in the cylinder, a plunger extending into the cylinder in position to be forced outwardly by the piston if the piston moves beyond its normal path of travel, a lever on which said plunger is adjustably mounted,

yieldinggmeans for connecting said lever with the valve, whereby when said plunger is forced out by the piston the valvewill be I moved to its limit in one direction, and a toothed rack located adjacent to said lever and in position to engage the lever and hold it in any position to which it is pushed by the piston, whereby the valve will also be v held in its limited position.

5. In a device of the character described, the combination with a cylinder and piston, of a valve for controllin the. operation ofthe piston in the cylin er, an adjustable plungerv extending into the cylinder to a point beyond the limit of the normal path of travel of the piston in position to be forced longitudinally of the cylinder by the piston only if the piston moves beyond its 110, normal'path of travel, a lever which said, plunger engages, and means for connecting said lever with the valve whereby when said plunger is forced out by the pistonthe valve will be moved in one direction. 1

.. 6. In a device of the character described,,, the combination with a cylinder and pistonof a valve for controlling the operation of 4 the piston in the cylinder, a plunger extend+ ing into the cylinder in position to be engaged and operated by the piston if the piston moves beyond its normal path of travel, and a connection between the plun- 'ger and valve for operating the valve, said connection comprising two-hooks, one extendmg 1n eacla direction, said hooks pro-,

jecting beyond each other, and a spring/ mounted between the hooks so as to be coin pressed by the operation of the plunger.

7.. In a steam engine cylinder having 3 steam-channels connecting its opposite'ends, In testimonywhereof we have hereunto and a controlling valve forthe 'steam-chanset our hands, in the presence of two sub- 10 nels; the combination of a tappet extending scribing witnesses.

into the cylinder, a lever supported bythe CHARLES W. GILMAN.

cylinder adapted to engage ,the tappet, ANIS L. WELCH, means connecting the lever and yalve, and Witnesses:

other means for holding the lever in a set v ALBERT E. FAY,

position. v CATHARINE IMELDA HARTNETT 

